Research on a technique of producing motion pictures utilizing a television system began long ago. But since the amount of information from a television system is insufficient and no excellent method was established for converting a video signal into a film image, there were only limited examples of application, and this technique did not come into widespread acceptance.
A high-grade television system and a laser film picture recording technique of unprecedented high performance have recently been developed, and a method of producing motion pictures utilizing them is of great interest.
The laser picture recording device consists of a laser light source, a light modulator, a light polarizer, a picture recording camera and a video process circuit. The principle of its operation is that three laser beams of red, green and blue whose intensities have been modulated in the light modulator according to video signals of three primary colors are synthesized into one beam by a dichroic mirror, horizontally polarized by the light polarizer, and then focused on a 35 mm film of the picture recording camera.
Details of this technique are described in Sugiura "35 mm Film Laser Picture Recording", Technical Report of the Society of Television, OPT169, pages 13 to 18 (1982). In laser film picture recording, a helium-neon (He Ne) laser (wavelength 632.8. nm) is used as a red color light source; an argon (Ar) laser (wavelength 514.5 nm), as a green color light source; and a helium-cadmium (He-Cd) laser (wavelength 441.6 nm), as a blue color light source. Color positive, color negative, and color internegative films for cinema are used for picture recording as described in the above-cited Technical Report.
These color positive, negative and internegative films, however, do not permit sufficient separation of colors among red-sensitive, green-sensitive and blue-sensitive emulsion layers with respect to the three types of laser light mentioned above (i.e., helium-neon, argon and helium-cadmium lasers). For example, if such a film is exposed to the argon laser (514.5 nm) Which is a green light source), the blue-sensitive and red-sensitive emulsion layers develop colors in addition to the green-sensitive emulsion layer, and color mixing occurs. Likewise, with the helium-cadmium laser (441.6 nm), a blue light source, the green-sensitive and red-sensitive emulsion layers develop colors in addition to the blue-sensitive emulsion layers, and color mixing occurs. If it is exposed to the helium-neon laser (632.8 nm), a red light source, blue-sensitive and green-sensitive emulsion layers develop colors in addition to the red-sensitive emulsion layer, and color mixing occurs.